Now Soros and his foundations have offered to match-fund further small donations up to £100,000 to the Best for Britain group, which wants to keep Britain in the European Union. Soros has already spent £400,000 on the campaign.

He told The Guardian: “I am happy to take the fight to those who have tried to use a smear campaign, not arguments, to prop up their failing case.”

The crowdfunding push has raised £59,625 so far. Best for Britain’s CEO Eloise Todd said: “We live in a democracy, and the right to freedom of speech is precious. Elements of the right-wing press don’t seem to agree.

“The UK’s future with the EU is not a done deal, there is still a vote to come and people across the country deserve to know the truth about the options on the table: one of which is staying and leading in the EU.

“George Soros and his foundations is kindly offering to help match-fund to give Best for Britain more support so we can make sure this message gets out: the biggest decision on Brexit is yet to come.”